btrfs: fix match incorrectly in dev_args_match_device
authorLiu Shixin <liushixin2@huawei.com>
Thu, 3 Nov 2022 08:33:01 +0000 (16:33 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 16 Nov 2022 08:58:27 +0000 (09:58 +0100)
commitc9fe4719c662e0af17eea723cf345e37719fd3c9
treeeb8d22ca28d5b31956a3537a5d78c79a3c43d135
parentf96fd36936310cefe0ea1370a9ae30e6746e6f62
btrfs: fix match incorrectly in dev_args_match_device

commit 0fca385d6ebc3cabb20f67bcf8a71f1448bdc001 upstream.

syzkaller found a failed assertion:

  assertion failed: (args->devid != (u64)-1) || args->missing, in fs/btrfs/volumes.c:6921

This can be triggered when we set devid to (u64)-1 by ioctl. In this
case, the match of devid will be skipped and the match of device may
succeed incorrectly.

Patch 562d7b1512f7 introduced this function which is used to match device.
This function contains two matching scenarios, we can distinguish them by
checking the value of args->missing rather than check whether args->devid
and args->uuid is default value.

Reported-by: syzbot+031687116258450f9853@syzkaller.appspotmail.com
Fixes: 562d7b1512f7 ("btrfs: handle device lookup with btrfs_dev_lookup_args")
CC: stable@vger.kernel.org # 5.16+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fs/btrfs/volumes.c